<!DOCTYPE html>
<html>
<head>
	<title>第一个js程序</title>
	<script type="text/javascript" src="hello.js"></script>
	<!-- <script type="text/javascript">
		window.onload = function(){
			//获取#btnId对应的元素节点
			var btn = document.getElementById("btnId");
			//为btn绑定单机响应函数
			btn.onclick=function(){
				//弹出警告框
				alert("hello");
			}
		}
	</script> -->
</head>
<body>
	<button id="btnId">sayhello</button>
</body>
</html>